1. Field of the Invention
The invention relates to a massage apparatus, more particularly to one that incorporates a single motor for operating a massage drive unit and for moving a slide frame upwardly and downwardly.
2. Description of the Related Art
In a conventional massage apparatus, a massage drive unit is mounted on a slide frame that is movable upwardly and downwardly. FIG. 1 illustrates a conventional massage apparatus that employs a single motor 15 to operate a massage drive unit 14 and to move a slide frame 13 upwardly and downwardly. The conventional massage apparatus includes an upright frame member 11 having a parallel pair of vertically extending guide rails 111. An externally threaded screw shaft 12 is mounted on the frame member 11 with the use of screw fasteners 113, and is disposed parallel to and between the guide rails 111. The slide frame 13 extends between the guide rails 111 and is coupled slidably thereto so as to be movable upwardly and downwardly therealong. The motor 15 is secured on a support 22 that is fixed to a lower frame part of the slide frame 13. The massage drive unit 14 is mounted on the slide frame 13. A coupling member 16 is mounted on a bracket 21 that is fixed to the lower frame part of the slide frame 13. The coupling member 16 is rotatable about a vertical axis, and is coupled threadedly to the screw shaft 12. The slide frame 13 further has an upper frame part provided with a screw guide 17 that permits extension of the screw shaft 12 therethrough.
The massage drive unit 14 includes an upright rotatable drive shaft 141. A lower end of the drive shaft 141 is provided with a drive gear 142. The motor 15 is coupled to the coupling member 16 on the screw shaft 12 via a transmission belt 18 for driving rotation of the coupling member 16 about the axis of the screw shaft 12. The coupling member 16 is coupled to the drive gear 142 via a transmission belt 19 for driving the drive shaft 141 to rotate axially.
With further reference to FIG. 2, the bracket 21 is a generally U-shaped bracket with parallel upper and lower bracket parts 211. The coupling member 16 is disposed rotatably between the upper and lower bracket parts 211, and is formed with a vertically extending screw hole 161 therethrough for threaded engagement with the screw shaft 12. The screw shaft 12 further extends through aligned holes 212 in the upper and lower bracket parts 211. The coupling member 16 is formed with an upper gear portion 162 for coupling with the transmission belt 18, and a lower gear portion 163 for coupling with the transmission belt 19. When the coupling member 16 is driven rotatably by the motor 15 via the transmission belt 18, because the screw shaft 12 is stationary relative to the frame member 11, the coupling member 16 will be able to move upwardly and downwardly along the screw shaft 12, thereby resulting in corresponding upward and downward movement of the slide frame 13 relative to the guide rails 111. Moreover, when the coupling member 16 rotates, the drive shaft 141 of the massage drive unit 14 also rotates by virtue of the engagement among the lower gear portion 163, the transmission belt 19 and the drive gear 142, thereby enabling a massaging roller assembly 143 of the massage drive unit 14 to impart a predetermined massaging action, such as a kneading or tapping massaging action.
Some of the drawbacks of the above-described conventional massage apparatus are as follows:
1. Sliding movement of the slide frame 13 and operation of the massage drive unit 14 are possible due to the presence of the coupling member 16. However, such an arrangement results in stress concentration on the coupling member 16, which can lead to rapid wearing of the same.
2. When replacing the transmission belts 18, 19 due to wear, it is necessary to remove the screw shaft 12 from the frame member 11, the coupling member 16 and the screw guide 17, and to remove the coupling member 16 from the bracket 21, thereby resulting in a great deal of inconvenience.